package com.shengdou.as.slopsapptest.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * Created by AS on 2017/8/25.
 */

public class SHA1 {

    public static String getStringSHA1(String str) {
        if (str == null || str.length() == 0) {
            return null;
        }

        char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA-1");
            mdTemp.update(str.getBytes("utf-8"), 0, str.length());

            byte[] md = mdTemp.digest();
            int j = md.length;
            char buf[] = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++) {
                byte byte0 = md[i];
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(buf);
        } catch (Exception e) {
            return null;
        }
    }

    //SHA1 加密实例
    public static String encryptToSHA(String info) {
        byte[] digesta = null;
        try {
// 得到一个SHA-1的消息摘要
            MessageDigest alga = MessageDigest.getInstance("SHA-1");
// 添加要进行计算摘要的信息
            alga.update(info.getBytes());
// 得到该摘要
            digesta = alga.digest();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
// 将摘要转为字符串
        String rs = byte2hex(digesta);
        return rs;
    }

    public static String byte2hex(byte[] b) {
        String hs = "";
        String stmp = "";
        for (int n = 0; n < b.length; n++) {
            stmp = (Integer.toHexString(b[n] & 0XFF));
            if (stmp.length() == 1) {
                hs = hs + "0" + stmp;
            } else {
                hs = hs + stmp;
            }
        }
        return hs;
    }

    //MD5加密实例
    public static String getMD5(String str) {
        MessageDigest md5 = null;
        try {
            md5 = MessageDigest.getInstance("MD5");
        } catch (Exception e) {
            e.printStackTrace();
            return "";
        }
        char[] charArray = str.toCharArray();
        byte[] byteArray = new byte[charArray.length];
        for (int i = 0; i < charArray.length; i++) {
            byteArray[i] = (byte) charArray[i];
        }
        byte[] md5Bytes = md5.digest(byteArray);
        StringBuffer hexValue = new StringBuffer();
        for (int i = 0; i < md5Bytes.length; i++) {
            int val = ((int) md5Bytes[i]) & 0xff;
            if (val < 16) {
                hexValue.append("0");
            }
            hexValue.append(Integer.toHexString(val));
        }
        return hexValue.toString();
    }
}
